You could start a topic, example "tkhooper and amma's PP Project" all of our pictures and comments would all be in one topic/thread. Everyone would start their own topic/thread for each of their own projects...that way they would be organized to each project started. These projects would then be posted by our names in the group activity section, as tkhooper explained.
Admin or the Moderators will be the deciding factor over whether these are kept in the Main section or moved to Pictures or Tutorials. I think deciding factor will be if the topic is in a tute format or a series of pictures as the projects are progressing, or if you are putting out a topic for general board discussion on a project.